Protective helmet



FIG. 1 is a front view of a protective helmet incorporating the design of the present invention;

FIG. 2 is a rear view of the protective helmet of FIG. 1;

FIG. 3 is a right side view of the protective helmet of FIG. 1;

FIG. 4 is a left side view of the protective helmet of FIG. 1;

FIG. 5 is a top view of the protective helmet of FIG. 1;

FIG. 6 is another front view of the protective helmet incorporating the design of the present invention, similar to FIG. 1, but with the visor in a lowered position;

FIG. 7 is a rear view of the protective helmet of FIG. 6;

FIG. 8 is a right side view of the protective helmet of FIG. 6;

FIG. 9 is a left side view of the protective helmet of FIG. 6; and,

FIG. 10 is a top view of the protective helmet of FIG. 6. 

The ornamental design for a protective helmet, as shown and described. 